2025/09/12 by Chun-Lin Xiao, Xue Li, Naohiro Okamoto +4 · 1 voice
Chemistry · Materials Science · #Luminescence and Fluorescent Materials #Supramolecular Chemistry and Complexes #Supramolecular Self-Assembly in Materials
paper · pdf · doi:10.1002/anie.202513783
openalex publication_date 2025/09/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/22
Rotaxanes, as one of the most fundamental mechanically interlocked molecules (MIMs), have attracted considerable attention in many fields. However, a method that reconciles convenient, efficient, and "high-value-added" (such as reversibility, higher-order structures, and diverse topologies) synthesis of rotaxanes, remains challenging. Here, we report a threading-and-shrinking strategy to quantitatively prepare [2]rotaxane and bis[2]rotaxane (higher than 99% conversion and 92% isolated yield for [2]rotaxane; 96% conversion, 80% isolated yield for bis[2]rotaxane). The rotaxanes with a chair-like and an orthogonal geometry were synthesized in one pot by 365 nm UV light irradiation via shrinkage of macrocycle driven by reversible topology transformation between nonhomeomorphic structures, requiring no extra addition of reagents like stoppers and catalysts. The heat-triggered reverse topology transformation quantitatively converts the chair-like rotaxanes into pseudo-rotaxanes to achieve mechanical unlocking. In contrast, rotaxanes with an orthogonal geometry exhibit thermal stability and remain mechanically interlocked upon heating.